Electro-polymer motor

ABSTRACT

An electro-polymer motor comprising a fixed member and a first actuator having a first end fixedly connected to the fixed member and a second end is presented. The first actuator comprises a polymer positioned between two electrodes. The electrodes are in communication with a power supply. The motor also comprises a driven member comprising a first leg and a second leg such that the first leg and the second leg are separated by an axis. The driven member is fixedly connected to the second end of the first actuator. The motor also comprises a compressible member having a first end fixedly connected to the fixed member and a second end fixedly connected to the second leg of the driven member. The compressible member is spaced apart from the first actuator. The first actuator elongates after the power supply applies a voltage across the electrodes to move the driven member.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication No. 61/090,306 filed on Aug. 20, 2008, entitled,“Electro-Polymer Motor”.

BACKGROUND OF THE INVENTION

The present invention relates, generally, to electro-polymer motors and,in particular, relates to electro-polymer motors that oscillate and/orpulsate a driven member in small appliances.

Electro-polymer motors typically have been used in robotics,lens-positioning and in pumps. Generally, these motors comprise a layerof polymer film situated between two conductive and elastic layers(i.e., electrodes). The polymer can be thought of as a dielectric. Thepolymer deforms in response to a voltage that is applied across the pairof electrodes, thereby, converting electrical power to mechanicalmovement.

BRIEF SUMMARY OF THE INVENTION

According to the present invention, an electro-polymer motor comprisinga fixed member and a first actuator having a first end fixedly connectedto the fixed member and a second end is presented. The first actuatormay comprise a polymer positioned between two electrodes. The electrodesmay be in communication with a power supply. The motor also may comprisea driven member comprising a first leg and a second leg such that thefirst leg and the second leg may be separated by an axis. The drivenmember may be fixedly connected to the second end of the first actuator.The motor also may comprise a compressible member having a first endfixedly connected to the fixed member and a second end fixedly connectedto the second leg of the driven member. The compressible member may bespaced apart from the first actuator. The first actuator may elongateafter the power supply applies a voltage across the electrodes to movethe driven member.

In accordance with another embodiment of the present invention, thepolymer may be pre-strained.

In accordance with another embodiment of the present invention, thefirst leg of the driven member and the second leg of the driven membermay be separated by a first angle across a central axis.

In accordance with yet another embodiment of the present invention, anelectric toothbrush comprises a head having a cleaning surface and ahandle connected to the head is presented. The handle may have a powersupply and a motor. The motor may comprise a first actuator having afirst end fixedly connected to the handle and a second end. The firstactuator may comprise a pre-strained polymer positioned between twoelectrodes. The electrodes may be in communication with the powersupply. The motor also may comprise a second actuator having a first endfixedly connected to the handle and a second end. The second actuatormay be spaced apart from and substantially parallel to the firstactuator. The second actuator may comprise a pre-strained polymerpositioned between two electrodes that may be in communication with thepower supply. The toothbrush also may comprise a driven membercomprising a first leg, a second leg and a shaft bearing positionedbetween and connected to the first leg and the second leg such that thefirst leg and the second leg may be separated by a first angle acrossthe shaft bearing. The first leg may be connected to the second end ofthe first actuator and the second leg may be connected to the second endof the second actuator. Finally, the toothbrush may comprise a shaft incommunication with the shaft bearing of the driven member. The first andsecond actuators may elongate in response to an applied voltage from thepower supply to oscillate, pulsate and/or linearly move the drivenmember and the shaft.

In accordance with still another embodiment of the present invention, amethod of electro-polymer motion is presented. The method may comprisealternately actuating a first pre-strained polymer actuator and a secondpre-strained polymer actuator with a oscillating pulse from a powersupply and oscillating a driven member by the actuation of the first andsecond actuators about an axis of the driven member.

In accordance with still yet another embodiment of the presentinvention, the power supply may supply a substantially concurrentpulsating pulse between the alternating oscillating pulses to producesubstantially concurrent oscillating and pulsing motion of the drivenmember about the central axis.

Accordingly, it is a feature of the embodiments of the present inventionto provide an electro-polymer motors in small appliances, such that thesmall appliances have the potential of being more cost-effective,lightweight, consume less power, and smaller. Other features of theembodiments of the present invention will be apparent in light of thedescription of the invention embodied herein.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The following detailed description of specific embodiments of thepresent invention may be best understood when read in conjunction withthe following drawings, where like structure is indicated with likereference numerals and in which:

FIG. 1A illustrates a schematic representation of an exemplaryelectro-polymer motor according to another embodiment of the presentinvention;

FIG. 1B illustrates a schematic partially rotated representation of theexemplary electro-polymer motor according to FIG. 1A;

FIG. 2 illustrates a perspective representation of an exemplarytoothbrush according to an embodiment of the present invention;

FIG. 3 illustrates a schematic representation of an exemplaryelectro-polymer motor according to an embodiment of the presentinvention;

FIG. 4A illustrates an exemplary digital oscillating voltage patternaccording to an embodiment of the present invention;

FIG. 4B illustrates an exemplary sinusoid oscillating voltage patternaccording to an embodiment of the present invention;

FIG. 5A illustrates an exemplary sinusoid voltage pattern for twodifferent oscillation frequencies according to an embodiment of thepresent invention;

FIG. 5B illustrates an exemplary digital voltage pattern for twodifferent oscillation frequencies according to an embodiment of thepresent invention;

FIG. 6A illustrates a schematic representation of an exemplaryelectro-polymer motor with one polymer actuator and a spring accordingto an embodiment of the present invention;

FIG. 6B illustrates a schematic representation of the exemplaryelectro-polymer motor with one polymer actuator and a spring in apartially rotated representation according to FIG. 6A;

FIG. 7 illustrates a schematic representation of an exemplary toothbrushaccording to an embodiment of the present invention;

FIG. 8 illustrates a perspective representation of an exemplary driveand driven member of a toothbrush according to an embodiment of thepresent invention;

FIG. 9 illustrates a cross-sectional view taken along A-A of theexemplary toothbrush drive system according to FIG. 8; and

FIG. 10 illustrates a cross-sectional view taken along B-B of theexemplary toothbrush drive system according to FIG. 9.

FIG. 11 illustrates another schematic representation of an exemplaryelectro-polymer motor with one polymer actuator and a spring accordingto an embodiment of the present invention.

FIG. 12 illustrates another schematic representation of an exemplaryelectro-polymer motor with two polymer actuators according to anembodiment of the present invention.

FIG. 13 illustrates still another schematic representation of anexemplary electro-polymer motor with two polymer actuators according toan embodiment of the present invention.

The embodiments set forth in the drawings are illustrative in nature andnot intended to be limiting of the invention defined by the claims.Moreover, individual features of the drawings and the invention will bemore fully apparent and understood in view of the detailed description.

DETAILED DESCRIPTION

The following text sets forth a broad description of numerous differentembodiments of the present invention. The description is to be construedas exemplary only and does not describe every possible embodiment sincedescribing every possible embodiment would impractical, if notimpossible, and it will be understood that any feature, characteristic,structure, component, step or methodology described herein can bedeleted, combined with or substituted for, in whole or part, any otherfeature, characteristic, structure, component, product step ormethodology describe herein. Numerous alternative embodiments could beimplemented, using either current technology or technology developedafter the filing date of this patent, which would still fall within thescope of the claims.

It should also be understood that, unless a term is expressly defined inthis patent using the sentence “As used herein, the term ‘_(——————)’ ishereby defined to mean . . . ” or a similar sentence, there is no intentto limit the meaning of that term, either expressly or by implication,beyond its plain or ordinary meaning, and such term should not beinterpreted to be limited in scope based on any statement made in anysection of this patent (other than the language of the claims). No termis intended to be essential to the present invention unless so stated.Unless a claim element is defined by reciting the word “means” and afunction without the recital of any structure, it is not intended thatthe scope of any claim element be interepreted based on the applicationof 35 U.S.C. §112, sixth paragraph.

In the following detailed description of the embodiments, reference ismade to the accompanying drawings that form a part hereof, and in whichare shown by way of illustration, and not by way of limitation, specificembodiments in which the invention may be practiced. It is to beunderstood that other embodiments may be utilized and that logical,mechanical and electrical changes may be made without departing from thespirit and scope of the present invention.

Referring initially to FIG. 1A, a schematic representation of anexemplary electro-polymer motor 10 is illustrated. The exemplaryelectro-polymer motor 10 may comprise a driven member 35, a firstactuator 20 connected between the driven member 35 and a fixed member15, and a compressible member 55 connected between the driven member 35and the fixed member 15. The fixed member 15 may optionally be part ofthe motor 10 or be a component separate from the motor 10 such as, forexample, a handle of a toothbrush (e.g., the handle 180 as shown ingreater detail in FIGS. 7-10).

The driven member 35 may comprise a central body 42, a first leg 40extending from the central body 42, and a second leg 45 extending fromthe central body 42 opposite the first leg. The first leg 40 and secondleg 45 may be symmetrically about a central plane 51. The central body42 may be disposed longitudinally along a longitudinal axis 50 of themotor 10, as seen in FIG. 2. The second leg 45 may be disposed radiallyabout the longitudinal axis 50 at an first angle 80 from the first leg40. The angle 80 may be between about 0 degrees to about 360 degrees,from about 30 degrees to about 180 degrees, or from about 45 degrees toabout 90 degrees. The driven member 35 may rotate clockwise and/orcounter clockwise about the longitudinal axis 50.

The central body 42 in this exemplary embodiment may comprise asubstantially cylindrical shape having a cylindrical shaped aperture 60disposed therethrough and coaxially-aligned with the longitudinal axis50. As such, the aperture 60 may be slid onto and attached to a driveshaft of a small appliance such as a toothbrush. The aperture 60 mayalso comprise a shaft bearing (not shown) as known to one of ordinaryskill in the art. In an alternative embodiment, the central body 42 mayintegrally form a portion of a drive shaft for a small appliance such asa toothbrush or be connected to such a drive shaft. In another exemplaryembodiment, illustrated in FIG. 3, the first leg 40 and second leg maybe substantially linearly aligned such that the first angle may besubstantially 180 degrees. It is understood that the first and secondlegs may comprise an integral unit.

The first leg 40, second leg 45, and central body 42 may all be asingle, integral component or may be three separate and distinctcomponents connected together using known means and methods to form thedriven member 35. As shown in FIG. 1A, the first leg 40 may comprise aproximal end 43 adjacent to the central body 42 and a distal end 41opposite the proximal end. Similarly, the second leg 45 may comprise aproximal end 44 adjacent to the central body and a distal end 46opposite the proximal end.

The distal end 41 of the first leg 40 may be fixedly connected to asecond end 24 of the first actuator 20 using a variety of known andunknown connection methods and devices, including but not limited towelds, sonic welds, adhesives, seaming technologies, brackets,laminating technologies and methods, combinations thereof, or the like.Although, shown connected to the distal end 41 of the first leg 40, itis understood that the first actuator 20 may be connected anywhere alongthe length and/or width of the first leg 40. A first end 22 of the firstactuator 20 may be fixedly connected to fixed member 15 using a varietyof known and unknown connection methods and devices, including but notlimited to welds, sonic welds, adhesives, seaming technologies,brackets, laminating technologies and methods, combinations thereof, orthe like.

As shown in FIG. 1A, the first actuator 20 may comprise a polymer 25positioned between a pair of electrodes 30. The pair of electrodes 30may be attached to the opposite surfaces of the first actuator 20 in avariety of known ways, including but not limited to adhesives, sonicwelds, mechanical connectors, coatings, combinations thereof, and thelike. The pair of electrodes 30 may be in communication with a powersupply (not shown). The pair of electrodes 30 may apply a voltage acrossthe polymer 25 resulting in the polymer 25 deforming (i.e., the polymer25 may expand and/or contract in response to the applied voltage) in amultitude of different directions (i.e., lengthwise, widthwise,diagonally, etc.). Polymers 25 and electrodes 30 suitable for use in thepresent invention are further described in U.S. Pat. Nos. 6,545,384 and6,781,284, which are herein incorporated by reference for all purposes.

The first actuator 20 may have a length (L) from about 0.1 mm to about200 mm, more specifically, the first actuator 20 may have a length fromabout 0.5 mm to about 150 mm and even more specifically first actuator20 may have a length from about 1 mm to about 100 mm. The first actuator20 may have a width from about 0.1 mm to about 80 mm, more specifically,the first actuator 20 may have a width from about 0.5 mm to about 60 mmand even more specifically first actuator 20 may have a width from about1 mm to about 40 mm. A single actuator 20 may have a thickness fromabout 1 μm to about 200 μm, more specifically a single actuator 20 mayhave a thickness from about 3 μm to about 150 μm, and even morespecifically a single actuator 20 may have a thickness from about 5 μmto about 100 μm. In another exemplary embodiment, more than one polymer25 may be laminated together to produce greater force for displacement.In this embodiment, the laminated polymers may have an overall thicknessfrom about 2 μm to about 20 mm, more specifically, the laminatedpolymers may have an overall thickness from about 20 μm to about 5 mm,and even more specifically, the laminated polymers may have an overallthickness of about 1 mm.

In one embodiment, the polymer 25 in the actuator 20 may bepre-strained. In one embodiment, the actuator 20 may be pre-strained byabout 0.1 to 60%. In another embodiment, the actuator 20 may bepre-strained by 2 to 20%. In still another embodiment, the actuator 20may be pre-strained by 10 to 15%. The amount of pre-strain (∈) maydepend on the relationship between the rotating angle (α) and the lengthof the lever arm (A₀) (i.e., the length of the first or second leg 40,45) using the following equation:

$ɛ = \frac{\Delta\; L}{L_{O}}$As illustrated in FIG. 1B, for example, to determine the amount topre-strain the polymer actuator, the following equations may be used.

$ɛ = {\frac{L_{1} - L_{0}}{L_{0}}\mspace{14mu}{and}}$$L_{1} = {\sqrt{L_{0}^{2} + {2\; A_{0}^{2}} - {2\sqrt{L_{0}^{2} + A_{0}^{2}}}}*A_{0}*{\cos( {\alpha + {\arctan( \frac{L_{0}}{A_{0}} )}} )}}$where ∈ is strain, α is the angle of deflection, L₀ is the length of thenon-deflected actuator and L₁ is the length of the deformed actuator.For example, if L₀=8 mm, A₀=5 mm, α=8°, L₁=8.7 mm are used, ∈ would be(8.7−8)/(8)=0.087 or 8.7%. By pre-straining, the polymer 20 may deformunidirectionally, for example, lengthwise.

The electro-polymer motor 10 may also comprise a compressible member 55having a first end 57 and a second end 59. The first end 57 may befixedly connected to the fixed member 15, and the second end 59 may befixedly connected to the distal end 46 of the second leg 45. The firstand second ends 57 and 59 may be connected to fixed member 15 and secondleg 45, respectively, using a variety of known and unknown connectionmethods and devices, including but not limited to welds, sonic welds,adhesives, seaming technologies, brackets, laminating technologies andmethods, combinations thereof, or the like. The compressible member 55may be spaced apart from the first actuator 20. Additionally, as shownin the exemplary embodiments in FIGS. 1-3, the compressible member 55may be spaced apart from and substantially parallel to the firstactuator 20 on an opposite side of the central plane 51. Although, shownconnected to the distal end 46 of the second leg 45, it is understoodthat the compressible member 55 may be connected anywhere along thelength and/or width of the second leg 45.

In an exemplary embodiment, the compressible member 55 may comprise asecond actuator, as is illustrated in FIG. 1. The second actuator 55 maybe comprised of a pre-strained polymer 65 positioned between a pair ofelectrodes 70, similar to the composition and configuration of the firstactuator 20. The pair of electrodes 70 may be also in communication withthe power supply (not shown).

When a voltage is applied across the pair of electrodes 30, the firstactuator 20 elongates from length L₀ to L₁ as illustrated in FIGS. 1Aand 1B. The deformation of polymer 25, in turn, causes the driven member35 to move. For example, the elongation of the first actuator 20 mayresult in the driven member 35 partially rotating about the longitudinalaxis 50 in response to the applied voltage (e.g., rotate counterclockwise). When the voltage is unapplied or removed from across thepair of electrodes 30, the polymer may return back to its normal state,i.e., un-deformed state (which may or may not include a pre-strainedstate). Thus, the returning of the polymer 25 to its normal state maycause the driven member 35 to rotate back the opposite direction aboutthe axis 50 (e.g., clockwise).

In other words, the applying and unapplying of voltage across the pairof electrodes 30 may cause the driven member 35 to oscillate about thelongitudinal axis 50. By oscillating, it is meant that the driven member35 partially rotates back (e.g., counter clockwise) and forth (e.g.,clockwise) about the longitudinal axis 50 in response to one or morepolymers (e.g., polymer 25) deforming. The polymer(s) may beelectrically activated to deform by applying an electrostatic fieldbetween the electrodes (e.g., pair of electrodes 30). The polymer 25 mayelastically deform in response to the voltage. Additionally, theelectrodes (e.g., pair of electrodes 30) may also elastically deformalong with the one or more polymers (e.g., polymer 25) in response tothe voltage.

The power supply may also alternate power between the first actuator 20and the second actuator 55 using an oscillating pulse resulting in thedriven member 35 rotating and/or oscillating about the longitudinal axis50. FIG. 4A illustrates an oscillating pulse voltage in a step functionthat may be delivered to the actuators. Specifically, the power supplymay apply a voltage across the pair of electrodes 30 while applying zerovoltage across the pair of electrodes 70, and then applying zero voltageto the pair of electrodes 30, while applying a voltage across the pairof electrodes 70. This alternating power may be repeated for any amountof time required to perform a task. Alternatively, FIG. 4B illustratesthat an oscillating pulse voltage in a sinusoidal function. Theoscillating pulse, in one exemplary embodiment, may apply a positivevoltage (the pulse wave above the x-line) to the first actuator 20 whilethe negative voltage (the pulse wave below the x-line) may be invertedand applied to the second actuator 55.

In one embodiment, the driven member 35 may have an angle of oscillation(α) of about 10 to about 80 degrees about the axis 50. In anotherembodiment, the driven member 35 may have an angle of oscillation (α) ofabout 4 to about 60 degrees about the axis 50. In another embodiment,the driven member 35 may have an angle of oscillation (α) of about 2 toabout 40 degrees about the axis 50.

Alternatively, the power supply may supply substantially concurrentpower to the first and second actuators 20, 55 using a pulsating pulseresulting in the driven member moving radially to the axis 50. Again,the pulsating pulse may be sinusoid. Further still, the power supply maysupply a substantially concurrent pulsating pulse between thealternating oscillating pulses to produce substantially concurrentoscillating and pulsating motion of the driven member 35 about the axis50. A controller (not shown) may control the amount of voltage the powersupply applies to the pairs of electrodes 30, 70. Additionally, thecontroller may control the frequency of the pulse pattern. Thecontroller may control the frequency to be between about 0.1 Hz to about150 kHz, or more specifically between 0.5 Hz to about 100 kHz, and evenmore specifically between 1 Hz to about 50 kHz. The controller may alsooverlay the oscillating and pulsating pulse frequencies to produce thesubstantially concurrent oscillating and pulsating motion of the drivenmember 35 as shown in FIGS. 5A and B.

In another exemplary embodiment, the compressible member 55 may be apre-strained spring 58, as illustrated in FIGS. 6A and 6B. As the firstactuator 20 elongates, the spring 58 may be compressed resulting in thedriven member 35 to rotate about the longitudinal axis 50 clockwise asshown in FIG. 6B. Again, as set forth above, when the voltage isunapplied across the pair of electrodes 30, the first actuator 20 mayreturn to its original, pre-strained state. As the first actuator 20returns to its original, pre-strained state, the spring 58 may cause thedriven member 35 to rotate about the longitudinal axis 50 back (e.g.,counter clockwise) to its original position as shown in FIG. 6A. Thus,the driven member 35 may oscillate about the longitudinal axis 50.

In still another embodiment, a third and fourth actuator (not shown) maybe connected between the fixed member 15 and the driven member 35. Theseactuators may be substantially parallel and proximate to the firstactuator 20 and the compressible member 55. Further still, a fifth andsixth actuator (not shown) may be connected between the fixed member 15and the driven member 35. These actuators also may be substantiallyparallel and proximate to the first and third actuator 20 and the fourthactuator and the compressible member 55. All the actuators and thecompressible member 55 may be separately or substantially concurrentlysupplied with a voltage across their respective electrodes from thepower supply

In yet another embodiment, the first actuator 20 may be comprised of twoseparate actuators positioned side-by-side lengthwise. Likewise, thecompressible member 55 may also be comprised of two or more separateactuators positioned side-by-side lengthwise. All the actuators may beseparately or substantially concurrently supplied with a voltage acrosstheir respective electrodes from the power supply. The power supply maysupply oscillating pulses or pulsating pulses to produce rotating,oscillating, pulsating and/or rolling motion.

Referring to FIGS. 7-10, an exemplary embodiment of the electro-polymermotor 10 (as shown in the figures and described herein) in use in asmall appliance, such as, for example, an electric toothbrush 200 isillustrated. The electric toothbrush 200 may comprise a head 190 havinga cleaning elements 195, a handle 180 connected to the head 190, a seal172, a motor 10, a drive shaft 170 connecting the motor 10 to either thehead 195 and/or the cleaning elements 195, a power supply 185 incommunication with the motor 10, a circuit board 182 in communicationwith the motor 10 and/or the power supply 185, and a charging coil 187.The seal 172, motor 10, drive shaft 170, circuit board 182, power supply185 and a charging coil 187 may all be disposed within the handle 180.

The toothbrush 200 may comprise any electric toothbrush,electromechanical toothbrush, manual toothbrush, oral cavity surfacebrush, combinations thereof, or any toothbrush as known to one ofordinary skill in the art. The cleaning elements 195 may comprisebristles, surfaces, elastomers, elastomeric surfaces, foams,combinations thereof, and the like. Some examples of suitable cleaningelements are disclosed in U.S. Patent Application Publication Numbers2002/0059685; 2005/0000043; 2004/0177462; 2005/0060822; 2004/0154112;U.S. Pat. Nos. 6,151,745; 6,058,541; 6,041,467; 6,553,604; 6,564,416;6,826,797; 6,993,804; 6,453,497; 6,993,804; 6,041,467; and U.S. patentapplication Ser. Nos. 12/008,073, filed on Jan. 8, 2008, entitled,“TOOTHBRUSHES” and 60/928,012, filed on May 7, 2007, entitled “ORALHYGIENE IMPLEMENTS”, all of which are herein incorporated by referencein their entirety.

The head 190 and handle 180 may comprise any number of known and unknownshapes, sizes, configurations, and materials. Exemplary materials forthe head 190 and handle 180 may include, but not be limited to,polymers, plastics, elastomers, metals, composites, or combinationsthereof (e.g., polypropylene, POM, ASA, ABS, PC, SAN, or any othersuitable material). The seal 172 may provide a waterproof barrierbetween the shaft 170 and the handle 180. The seal 172 may protect themotor 10, circuit board 182 and power supply 185 in the handle 180 fromthe conditions outside the handle 180. The seal 172 may be comprised ofa polymer, rubber, or any material known in the art.

The motor 10 may be powered by the power supply 185 and may be operableto provide movement to the head 190 and/or the cleaning elements 195,including but not limited to oscillating, pulsating, and/or linearmovement. In this exemplary embodiment, illustrated in FIG. 10, thefirst actuator 110 and second actuator 112 may each comprise apre-strained polymer positioned between a pair of electrodes as shownand described above herein. The pair of electrodes of each of theactuators may be in communication with the power supply 185. As such,the actuators 110, 112 are operable to receive voltage from the powersupply 185 individually or simultaneously. Additionally, the firstactuator 110 and second actuator 112 of the motor 10 may be fixedlyconnected to the handle 180 at one end of the actuators 110, 112.Further, the first actuator 110 and second actuator 112 of the motor 10may be fixedly connected to a driven member 120 at the other end of theactuators 110, 112.

The toothbrush 200 may comprise a drive shaft 170 that is incommunication with the driven member 120 as illustrated in FIG. 8. Inone exemplary embodiment, illustrated in FIG. 10, the drive shaft 170may be integral with the central body 42 of the motor 10 by sliding andattaching the cylindrical shaped aperture 60 of the motor 10 on to thedrive shaft 170 as described herein.

A cleaning attachment 190 may be in communication with the drive shaft170 as shown in FIG. 8. In one exemplary embodiment, the cleaningattachment 190 may comprise a head 195 and a neck 197 and may bereplaceable as illustrated in FIG. 9. In another exemplary embodiment,just the head 195 of the cleaning attachment 190 may be replaceable. Inone exemplary embodiment, the head 195 may comprise cleaning elementsfor the toothbrush 200 as illustrated in FIG. 8.

Turning back to FIG. 8, the exemplary toothbrush 200 may furthercomprise a front bearing 150 that may be connected to the handle 180 andthe driven member 120 and that may encompassed the drive shaft 170. Thefront bearing 150 may serve as a pivot point for the drive shaft 170during pulsating motion. Additionally, the toothbrush 200 may alsocomprise a back bearing 160 that may be flexible about the drive shaft170. The back bearing 160 may be flexibly mounted to the handle 180 topermit an alternative or superimposing pivoting motion by the driveshaft 170 about the front bearing 150 during oscillating motion.

The first and second actuators 110, 112 in the toothbrush 200 mayelongate in response to an applied voltage from the circuit board 182 tooscillate, pulsate and/or linearly move the driven member 120 and thedrive shaft 170. If the circuit board 182 supplies alternates power tothe first and second actuators 110, 112 (i.e., sends an oscillatingpulse), the drive shaft 170 may oscillates. Alternatively, if thecircuit board 182 supplies substantially concurrent power to the firstand second actuators 110, 112 (i.e., sends a pulsating pulse), the driveshaft 170 may pulsates. Further, if an oscillating pulse is overlaidwith a pulsating pulse, the drive shaft 170 may both oscillate andpulsate.

In one embodiment, the power supply 185 may be a rechargeable battery.In another embodiment, the power supply 185 may be in the form of an A/Cadapter. However, any suitable power supply known in the art may beused.

The circuit board 182 may contain the electronic components thatcomprise a controller and a voltage converter as is well known in theart. The controller as described herein may control the voltageconverter as well as the amount of voltage the power supply 185 appliesto the electrodes of the motor 10 as well as the frequency of a pulsepattern and the shape of the pulse pattern.

In one exemplary embodiment, the toothbrush 200 may have a switch (notshown) to allow an operator to switch between the drive shaft 170oscillating, the drive shaft 170 pulsating or the drive shaft 170oscillating and pulsating concurrently. The switch my be a pushbutton, atoggle switch, or any other suitable type switch known in the art.Alternatively, in another exemplary embodiment, the power supply 185 mayswitch the type of power supplied to the actuators 110, 112 between thedrive shaft 170 oscillating, pulsating or both oscillating and pulsatingpassed on a predetermined passage of time. For example, the toothbrush200 may switch the mode of operation to indicate to the operator thatthe toothbrush 200 should be moved to another quadrant of the mouth orto indicate that a sufficient amount of brushing time has elapsed. Theuse of electro-polymer motors in small appliances, such as, for example,electric toothbrushes, as shown and described above herein, may have thepotential of being more cost-effective, lightweight, consume less power,and smaller.

FIG. 11 illustrates another schematic representation of an exemplaryelectro-polymer motor 10 with one polymer actuator 20 and a spring asthe compressible member 55. In this exemplary embodiment, thecompressible member 55 may be spaced apart from and substantiallyparallel to the first actuator 20 on the same side of the longitudinalaxis 50 of the driven member 35. The first actuator 20 elongates after apower supply applies a voltage to the first actuator 20 to move thedriven member 35 as described above.

FIG. 12 illustrates another schematic representation of an exemplaryelectro-polymer motor with one polymer actuator 20 and a second actuatoras the compressible member 55. In this exemplary embodiment, the secondactuator 55 may be spaced apart from and substantially aligned along thesame plane of the first actuator 20 on an opposite sides of the drivenmember 35. Both the first actuator 20 and the second actuator 55 may bepositioned on the same side of the longitudinal axis 50 of the drivenmember 35. The first actuator 20 may be connected to the driven member35 and a first fixed member 15. The second actuator 55 may be connectedto the driven member 35 and a second fixed member 1200. The firstactuator 20 elongates after a power supply applies a voltage to thefirst actuator 20 to move the driven member 35 as described above.Alternatively, a voltage may also be applied to the second actuator 55,substantially concurrently or alternatively, to the voltage that mayapplied to the first actuator 20.

FIG. 13 illustrates still another schematic representation of anexemplary electro-polymer motor with one polymer actuator 20 and asecond actuator as the compressible member 55. In this exemplaryembodiment, the driven member 35 may be substantially triangular shaped.The first actuator 20 elongates after a power supply applies a voltageto the first actuator 20 to move the driven member 35 as describedabove. Alternatively, a voltage may also be applied to the secondactuator 55, substantially concurrently or alternatively, to the voltagethat may applied to the first actuator 20.

It is noted that terms like “preferably,” “commonly,” and “typically”are not utilized herein to limit the scope of the claimed invention orto imply that certain features are critical, essential, or evenimportant to the structure or function of the claimed invention. Rather,these terms are merely intended to highlight alternative or additionalfeatures that may or may not be utilized in a particular embodiment ofthe present invention.

For the purposes of describing and defining the present invention it isnoted that the term “substantially” is utilized herein to represent theinherent degree of uncertainty that may be attributed to anyquantitative comparison, value, measurement, or other representation.The term “substantially” is also utilized herein to represent the degreeby which a quantitative representation may vary from a stated referencewithout resulting in a change in the basic function of the subjectmatter at issue.

All documents cited in the Detailed Description of the Invention are, inrelevant part, incorporated herein by reference; the citation of anydocument is not to be construed as an admission that it is prior artwith respect to the present invention.

Having described the invention in detail and by reference to specificembodiments thereof, it will be apparent that modifications andvariations are possible without departing from the scope of theinvention defined in the appended claims. More specifically, althoughsome aspects of the present invention are identified herein as preferredor particularly advantageous, it is contemplated that the presentinvention is not necessarily limited to these preferred aspects of theinvention.

1. An electro-polymer motor, the motor comprising: a fixed member; afirst actuator having a first end fixedly connected to the fixed memberand a second end, the first actuator comprising a polymer positionedbetween two electrodes, wherein the electrodes are in communication witha power supply; a driven member comprising a body having cylindricalshape with a cylindrical shaped aperture disposed therethrough, whereinthe driven member is fixedly connected to the second end of the firstactuator; and wherein the body is disposed longitudinally along alongitudinal axis of the motor and the aperture is coaxially alignedwith the longitudinal axis; and a compressible member having a first endfixedly connected to the fixed member and a second end fixedly connectedto the body of the driven member, the compressible member spaced apartfrom the first actuator; wherein the first actuator changes length afterthe power supply applies a voltage across the electrodes to move thedriven member.
 2. An electro-polymer motor, the motor comprising: afixed member; a first actuator having a first end fixedly connected tothe fixed member and a second end, the first actuator comprising apolymer positioned between two electrodes, wherein the electrodes are incommunication with a power supply; a driven member comprising a firstleg and a second leg both extending from a central body such that thefirst leg and the second leg are separated by an axis, wherein thedriven member is fixedly connected to the second end of the firstactuator; wherein the body has a cylindrical shape with a cylindricalshaped aperture disposed therethrough; and wherein the body is disposedlongitudinally along a longitudinal axis of the motor and the apertureis coaxially aligned with the longitudinal axis; and a compressiblemember having a first end fixedly connected to the fixed member and asecond end fixedly connected to the second leg of the driven member, thecompressible member spaced apart from the first actuator; wherein thefirst actuator elongates after the power supply applies a voltage acrossthe electrodes to move the driven member.
 3. The motor of claim 2,wherein the elongation of the first actuator oscillates the drivenmember about the axis.
 4. The motor of claim 2, wherein the drivenmember further comprises a shaft bearing along and about the axis andpositioned between the first and second legs.
 5. The motor of claim 2,wherein the polymer is electrically activated by applying anelectrostatic field between the electrodes.
 6. The motor of claim 2,wherein the polymer elastically deforms in response to the voltageapplied to the electrodes.
 7. The motor of claim 2, wherein the polymerelastically deforms in response to the voltage applied to the electrodesin one direction.
 8. The motor of claim 2, wherein the polymer and theelectrodes both elastically deform in response to the voltage applied tothe electrodes.
 9. The motor of claim 2, wherein the polymer comprisesmore than one polymer layer, wherein the more than one polymer layersare laminated together.
 10. The motor of claim 2, wherein the firstactuator is pre-strained by about 0.1% to about 40%.
 11. The motor ofclaim 2, wherein the first actuator is pre-strained by about 2% to about20%.
 12. The motor of claim 2, wherein the first actuator ispre-strained by about 10% to about 15%.
 13. The motor of claim 2,wherein the compressible member comprises a pre-strained spring.
 14. Themotor of claim 13, wherein the spring compresses as the first actuatorelongates resulting in the driven member oscillating about the axis. 15.The motor of claim 2, wherein the compressible member comprises a secondactuator comprising a pre-strained polymer positioned between twoelectrodes, wherein the electrodes are in communication with the powersupply.
 16. The motor of claim 15, wherein the power supply alternatespower to the first and second actuators resulting in the driven memberoscillating around the axis.
 17. The motor of claim 15, wherein thepower supply supplies substantially concurrent power to the first andsecond actuators resulting in the driven member moving radially to theaxis.
 18. The motor of claim 15, further comprises a third actuatorsubstantially parallel and proximate to the first actuator; and a fourthactuator substantially parallel and proximate to the second actuator.19. The motor of claim 18, further comprises a fifth actuatorsubstantially parallel and proximate to the first actuator and the thirdactuator; and a sixth actuator substantially parallel and proximate tothe second actuator and the fourth actuator.
 20. The motor of claim 2,wherein the driven member has an angle of oscillation of about 2 toabout 40 degrees about the axis.
 21. The motor of claim 2, wherein thepower supply supplies pulsed voltage to the electrodes.
 22. The motor ofclaim 2, wherein the power supply supplies a substantially sinusoidaldrive voltage pattern to the electrodes.
 23. The motor of claim 2,further comprises a controller to control the amount of voltage thepower supply applies to the electrodes and the frequency of a pulsepattern.